1. Field of the Invention
The present invention relates to a unique method for preparing and applying a lightweight cementitious coating to existing and/or new roof surfaces. By virtue of the method of the present invention, the roof coating provides an extremely durable, light-weight and attractive roof surface.
2. Description of the Prior Art
Today, various kinds of coatings or coverings for roof structures are well known. Of course, perhaps the most common type of roof coating or covering material is asphalt-type shingles. Of course, particularly in warm climates, clay and ceramic tiles are also utilized as roof coatings. Another type of roofing material is generally referred to in the building industry as builtup gravel. This type of roofing construction is prepared by the application of a tar, or asphalt base onto which loose gravel is scattered. Finally, more modern structural building techniques have resulted in the construction and application of roofing materials comprising sheets of metal, fiberglass, plastic, or other such synthetic materials.
As a result of the energy crisis of recent years, it has also become common practice to apply a coating to existing roof structures for the specific purpose of increasing the insulative capabilities of the roof as well as for the purpose of reflecting the sun's rays. Certain problems have been identified with such roof coatings. In the first place, in order to effectively increase the insulative capabilities of the roof, it is often necessary to add such a heavy coating as to create structural complications. That is to say, it may be necessary to add further reinforcement to the roof construction from within before the coating can be applied. Furthermore, since insulating materials are normally of relatively low density, it is often necessary to add yet a second coating on top of the insulating medium. In the case of roof coatings specifically designed for reflecting the sun's rays, the coating often comprises nothing more than a layer of white, or light-colored paint. In this case, the homeowner is then faced with the requirement of having to maintain a relatively large painted surface.
Accordingly, it is clear that there is a great need in the art for a method of coating either existing or new roof structures with a relatively lightweight material such that the roof will be provided with a durable, attractive surface. So that the coating may be utilized in a variety of structural applications, it would be further desirable if it could be applied either manually, as by trowelling or spreading, or by pumping the coating material to the roof sides. Of course, the method for coating the roof must be suitable for use either in new installations or in covering existing roofs.